Radiators not getting hot downstairs - power flushing?

[tiptoe]

Hi,

We got a heating engineer to install 30m2 of water underfloor heaiting in our house. The house has 2 floors with 8 radiators. The 2 radiators downstairs are not heating up but it was all working fine before. The ones upstairs are very hot and getting a lot of air. The underfloor heating is working nicely and is independently control.

The 2 downstairs stopped working about 2 weeks ago after he connected the underfloor heating pipes to the boiler. He came back the next day add got the downstairs radiators to work again and they worked for about 3 days. Now they dont.

The engineer is away but I spoke to him yesterday and followed his instructions to remove the RTV, move the pins, close the hot water and all other radiators. The radiators got a bit warm but not much at all and then cold again.

His assessment is that we should call in someone to presurise the system and power flush it as he thinks there must something blocking in the pipework - and by pressurising it we will solve the problem of the air going in the system and having to bleed the rads. He does not think it is the pump. The hot water goes from the boiler to the upstairs rads before going downstairs.

What do you think?

Thank you

Tom

 

[bobw1956]

get the pump checked first

 

[JohnD]

The 2 radiators downstairs are not heating up but it was all working fine before. The ones upstairs are very hot and getting a lot of air.

Turn off whatever is too hot and see if whatever is too cold then warms up. If you you have a balancing problem which is very common and very easy to fix.

"A lot of air?" Do you have an open vented system with a feed and expansion tank in the loft? If so go and feel it to see if it is hot, and if water comes out of the vent pipe bent over the top. How much mud is in it? What colour?

What anti-corrosion chemical did your installer add when refilling?

How did you choose your installer, and what do you know about his qualifications and experience? Why is he leaving you to find someone else to solve the problems caused by his installation? Did you do it yourself or did you pay someone?

 

[petit_pablo]

Sounds airlocked to me.

Turn all other rads and the UF off and let the pump push the air out. It will help to do 1 rad at a time rather than both that dont work together.